1. Field of the Invention
This invention relates to collapsible trailer hitches of the type used to retain highway cargo trailers on railway cars or ship decks. The invention specifically relates to pivot mounts for attaching the collapsible hitch to a deck or support surface.
2. Description of the Prior Art
Fifth wheel hitch assemblies used to support cargo trailers hauled on railway cars maintain the trailers positioned on the cars by attachment to the kingpin of the trailer. These support assemblies are collapsible to enable the assembly to retract away from the trailer onto the deck of the railway car so a tractor equipped with a fifth wheel can engage the kingpin and remove the trailer from the railway car. Due to the need for collapsibility these support assemblies are pivotally mounted to the deck or support surface of the railway car by pivot mounts rigidly attached to the railway car. These mounts are subjected to severe force loadings, particularly during abrupt accelerations and decelerations of the railway car while the support assembly is supporting a heavily laden cargo trailer. Past efforts to strengthen the pivot mountings for the support struts have included the need to rigidly attach gussets from the inner sides of the box sill members of the railway car to the pivot mountings as well as to the outside of the box sill members. The need to attach gussets to the inner surfaces of the box sill members and the pivot mountings entails undesirably complicated and costly construction to enable the pivot mountings to transfer strut loadings from the support struts through the pivot mounts to the box sill members without damage to, or failure of, the pivot mountings.
U.S. Pat. No. 3,653,621 shows an angle shaped member which serves as a connective member between the components of a pivot bracket or mount.